Accounting software star Xero has teamed up with farm software specialist Figured to develop a single cloud-based software service that will let farmers manage their accounts and their farms online.

Xero said the "farming in the cloud" service would be available by the middle of the year and would combine its accounting software with Figured's tools to manage livestock reporting and farm budgeting.

"Farming is the backbone of our nation and Xero is committed to working with farmers, their advisers and stakeholders to lift the future of farming productivity," Xero rural strategy leader Ben Richmond said.

The service would let farmers, accountants, banks and rural service companies work together from the same data, providing a central home for accounting and farm management tools, he said.

Xero would work with Vodafone to provide the service and had formed a partnership with agricultural services firm PGG Wrightson, he said.

Figured said farming threw up "quite unique" accounting challenges, such as tracking a "living inventory" of livestock, which meant farm management and accounting had been largely disconnected.

Its project director, Duncan Anderson, said there had been overseas interest in the service and there were no barriers to its international use.

Earlier today, Xero announced it was a quarter of the way to chief executive Rod Drury's medium-term goal of signing up a million customers.

The company announced it had notched up 250,000 customers as nearly 900 accountants and software partners gathered for its annual "Xerocon" conference in Auckland today.

Xero said it had passed the milestone late last month.

Drury said he was pleased with the company's progress, given it took Xero five years to notch up its first 50,000 customers.

"In the last 12 months we've added 115,000. We are gaining real momentum," he said.

Xero announced late last month that with results in for the first three-quarters of its 2013-14 financial year, it was just on target to achieve the 80 per cent-plus annual sales growth Drury forecast at the company's annual meeting in August.

Chief revenue officer Stuart McLean has sold 6000 shares - about 7 per cent of his total holdings - at just over $40-a-share, Xero also announced to the NZX.